1. Field of the Invention
The present invention relates to a cleaning and drying apparatus which cleans objects to be processed, such as semiconductor wafers and LCD (liquid crystal display) glass substrates etc., by immersing them in cleaning liquid, for example chemicals and rinsing liquids, and thereafter, dries the objects.
2. Description of the Related Art
Generally, in the field for producing semiconductor devices, there is a widely adopted cleaning process where the objects to be processed, such as semiconductor wafers and LCD glass substrates etc.(referred to "wafers etc." hereinafter), are successively immersed in a process bath filled up with the chemicals, the rinsing liquids or the like. In addition, there is also known a drying apparatus which dehydrates and dries the wafers etc. by contacting the surfaces of the wafers etc. after cleaning with dry gas of vapor of volatile organic solvent such as IPA (isopropyl alcohol) etc., for condensation or absorption of the vapor of the dry gas on the surfaces.
The conventional cleaning and drying apparatus mentioned above includes a drying section arranged above a cleaning section storing the cleaning liquid of the chemicals, the rinsing liquids or the like, and a shutter for opening and closing a communication port between the cleaning section and the drying section. In this cleaning and drying apparatus, after the wafers to be processed have been delivered from a conveying arm carrying the wafers to carrying means through the opened communication port, the wafers are cleaned in the cleaning section while withdrawing the conveying arm. After cleaning, the wafers are pulled up from the cleaning section and transferred into the drying section. Then, the cleaning section is separated from the drying section by closing the communication port by the shutter and thereafter, the dry gas is supplied into the drying section to dry the wafers.
In the above-mentioned conventional cleaning and drying apparatus, however, since the sealing about the shutter is undertaken by sealing members, for example O-rings etc., there still remains a possibility that the sealing between the cleaning section and a driving part for opening and closing the shutter is not accomplished perfectly, so that particles produced in the driving part enter into the cleaning section. In addition, there is also a possibility that an atmosphere in the cleaning section enters into the driving part, so that the performance of the driving part is influenced and the life span of the apparatus itself is reduced, disadvantageously.
Again, it should be noted that the above-mentioned drying apparatus is constructed so as to accommodate the plural wafers etc. in a drying chamber while being apart from each other at regular intervals in the horizontal direction and adapted so as to blow the dry gas against the wafers etc. through dry gas supplying means, such as gas nozzles, disposed in the drying chamber in order to dehydrate and dry the wafers etc.
In the so-constructed drying apparatus, however, since the above dry gas supplying means is fixed in a position, it is hard to supply the dry gas all over the surfaces of the wafers etc. uniformly. Thus, because of its unequal drying of the wafers etc., it may cause the drying efficiency to be deteriorated. Additionally, since a lot of dry gas is required to supply the dry gas all over the surfaces of the wafers etc., there are problems of increasing the gas consumption and requiring much time for the drying process.